Traction wheel



B. R. BENJAMIN TRAGTION WHEEL Filed May 26 1922 Patented `lully 22, 1924..

UNITED STATES irA'i'ENA forros.

BERT R. BENJAMIN, OF OAK PARK, ILLINOIS, ASSIGNOR TO INTERNATIONAL HAR- VESTER COMPANY, 0F CHICAGO, ILLINOIS, A CORPORATION 0F NEWT JERSEY.

' 'rRAo'rIoN WHEEL.

Application filed May 26,

ticularly to a traction wheel adapted forv use as a drive wheel on tractors and agricultural implements such. as mowers, binders, headers, etc.

Tractors and agricultural implements must be used on ground varying greatly in hardness and resistance. In order to obtain suliicient traction in soft ground, it has been customary to secure traction lugs to the periphery of the wheels which penetrate the ground and offer the necessary resistance to propel the vehicle or the operative parts of the implement. Such wheels usually have plain cylindrical rims to which the lugs are secured by'bolts or rivets and, when operating in soft or sticky ground, the spaces between the lugs soon become packed full with earth or mud so that most of the traction is lost. Also when operating on firmer ground, the lugs penetrate to their full depth, if at all, which gives more traction than necessary and also cuts up or destroys the hard surfaces of roadways.

Having in mindthe above noted difficulties, I have invented a traction wheel that will run on hard roads without injury thereto and yet is adapted without change to penetrate ground of varying degrees of hardness to a depth suilicient to afford the necessary traction, the contour of the wheel rim and relation of the lugs being such that the wheel is self-cleaning in sticky ground, that is, the spaces between the lugs will not pack full.

The traction wheels of agricultural imple- 1 ments are usually made from cast iron which has very little tensile strength but is coniparatively strong under compression. In order that my improved wheel may be advantageously used in cast form, I have distributed tlie metal in the rim so that the tensile stresses are resisted by a relatively large cross-sectional area and the compression stresses resisted by a much smaller area, thereby distributing the metal so that the 1922. serial No. 563,962.

strength of the wheelris a maximum for any i f given size or weight.

In the drawings, I have illustrated an einbodiment of my invention in what `I now believe to be its best form.

Fig. l is a plan View; and

2 is apart side elevation of a preferred form of wheel;

Fig. 3 is a 2; and

Fig. 4 isa section corresponding to 3 of a modified construction.`

The wheel has a hub 5 and anannular rim 6 connected thereto by spokes .7 preferably cast integrally therewith. The. rim-has a central radial Piange or rib 8 increasing slightly in thickness from-its outer'edgc to the base where it is joined to the rim 'by fillets 9, 10. Traction lugs 1l, 12 are provided on each side of the rib and are of the same height but project laterally beyond the edges of the rim. f'

l/Vhen the wheel is traveling onthe road or hard ground, it' rides on the rib. 8 and outer edges of the lugs with little or no'penetration but when on softer ground, the rib 8 and lugs will penetrate to a suficient depth to support the load, the resistance to penetration increasing Vwith the depth and at the saine time increasing the traction proportional to the depth that vthe lugs penetrate. Thus when the ground permits little penetration, its resistance will give sufficient traction to the lugs to propel the tractor or drive the implement. While if the ground be softer, the flange and lugs will sink deeper so that sulicient traction is obtained. If the ground be so soft that the penetration of the lugs and flange to their full depth is not suliicient to sustain the load, the rim 6 will stop further penetration and the broad lugs will afford suliicient traction for substantially all purposes.

`When the wheel is being used on muddy or sticky ground, the earth will tend to gather in pyramidal form with its apex at the outer end of the rib and its base on the rim but it cannot lill up between the lugs because, as it accumulates, it will4 be crowded off at the edge of the rim when the rib again enters the ground.

In the modification shown in Fig. 4, the rim 6', spokes 7', rib 8", and lugs 1l', 12 are similar in all respects tothe correspondsection on the line 3 3l of Fig. I

the same conditions t-he modiied form may penetrate only one-halt the depth of the lugs due to the greater support offered by t-hethickened rib.

An important advantage of my invention is that it may be cast in a two-part mold without the use of cores of any kind, the

cost ot production being very much reduced thereby.

Another decided advantage is the distribution of the metal in the rim whereby maximum strength is secured. A cross section of the rim is substantially a 'lsec'tioin the rim 6 or 6 which is under tension when the wheel is loaded forming the head of the T and the rib 8 or 8 which is under compression forming the leg oi" the T. The

, metal is therefore distributed so as to give maximum strength since the greater amount of metal distributed in the head of the T resists the tensile strains and the lesser cross section of the rib resists the stresses due to compression.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. 'As Aan article 'of vnanufacture, a 'tracmorse? curve into the rim, and radial traction lugs Iifi secured in staggered rela-tion on opposite sides ot the rib and to the rim andextending laterally beyond the rim.

2. As an article of manufacture, a wheel having a rim cast in one piece7 the rim be- 2 ing a T-section with the. head of the T disposed inwardly and the leg extending radially outward and having traction lugs of the same height as the leg and extending later ally beyond the head on opposite sides.

As an article ot manufacture5 a traction Wheel having `a rim, a centrally dis posed rib extending radially outward theretrom and of gradually decreasing thickness7 radial traction lugs ofthe same height as the rib secured to opposite sides thereof and to the rim'f-andexte'nding laterally beyond the rim.

4. As an article of manufacture, a traction wheel having a rim, a centrally disposed rib ofi gradually decreasing thickness extending radially outward therefrom, the sides of the rib merging into the outer tace of .the rim, radial traction lugs of the same height-as the rib secured to opposite sides thereof andto the rim and extending later ally beyond the rim. Y

In testimony whereof l aiiix my signature.

BERT R.' BENJAMN. 

